Currently, the delivery of multimedia content like video and live programs, not only happens via cable networks and DTH (direct to home), but are increasingly moving towards IP (internet protocol) based delivery of multimedia content. Consumers today may seek for a personalized & interactive video watching experience. MPVDs (Multi-programming Video Distributors) are increasingly switching to IP based video or any multimedia content delivery, to build an immersive video viewership base. Now, with the spike in number of users, there is a varied demand in a number of multimedia content and hence congestion in any downstream network bandwidth. With the launch of OTT (over the top content) services, in many situations, MPVDs do not have full control of the downstream network causing network congestion and hence inferior quality of the multimedia content may be delivered to an end user.
Also, improving the access to network bandwidth alone will not solve the problem of network congestion, since the “core” and “aggregate” networks usually have fixed bandwidth pipes. Moreover, it is much more tedious and cost prohibitive to perform regular network upgrades for bandwidth expansion. Hence, for efficient delivery of multimedia content, there is a requirement for dedicated streams for every user, resulting in random fluctuations on available network bandwidth at any given point of time. This results in unpredictable variations in quality of video streams being served to users which may end up in poor customer experience.
However, in spite of several advancements in multimedia content delivery technologies, delivering best-in class video quality over IP networks, especially for live video streaming, still presents a host of challenges. Significant amongst these challenges are network delays/jitters and packet losses due to network congestion. Across any multimedia content delivery pipeline, a multimedia content streaming losses occur in the network where the content is delivered from the CDN (content delivery network) edge caches to consumer devices viz. mobile phones, tablet form factors, Smart TVs an STBs.
Adaptive Bitrate Streaming (ABR) partially addresses the streaming challenges on networks with uncertain bandwidth. The core problem of preventing downstream network congestion due to an increased traffic in proportion to a number of users (streams increases proportionately with increase in user request) and consequently there is a reduction in available bandwidth. ABR is largely a mechanism that helps improving user perception of content quality, in networks with uncertain bandwidth by switching to lower bitrate streams smoothly but does not address the core problem of minimizing traffic congestion for live streaming. Further, unlike on demand streaming over IP, live streaming does not necessarily require dedicated unicast streams all across the delivery networks, typically 1 per user per device. This system of unicast delivery may be avoided. Currently, live streaming techniques such as ABR relies on HTTP as a streaming protocol. Though HTTP based streams can easily be delivered over CDN (Content Delivery Networks) through cache-replication, they render themselves difficult to be delivered over multicast (UDP based protocol).